SMTP is the Simple Mail Transfer Protocol, the most recent standard of which is defined in RFC 5321. It's the Internet standard for sending and receiving email.

learn more… | top users | synonyms

0
votes
1answer
543 views

Exim as relay server

Hi I have exim running on port 8900 and another mail server running on port 25. This mail server will be used to relay outgoing emails to exim. But somehow I am getting this error from exim 550, '...
0
votes
2answers
750 views

Is it safe to ublock 587, SMTP submission port?

We have had problems before with SMTP port 25 (smtp) - some PC's were sending spam mail throught that port. So we blocked that and only allowed only outgoing smtp servers we needed. Howerver, i read ...
-1
votes
4answers
5k views

Postfix setup on AWS EC2 using SMTP relay

On ec2 instance, the IP is dynamic, and if I want to use third party SMTP gateway such as sendgrid, what is the suggested values of the following fields? myorigin myhostname mydestination Assume ...
-1
votes
3answers
5k views

550 Requested action not taken: mailbox unavailable

I setup a small box with Server 2003 64bit to be used as a webserver and email server for a small school. Real simple stuff for a few users. A simple website and a handful of emails. rDNS and spf ...